The Senate Finance Committee washed its hands of the controversy over a "superfund" to clean up chemical dumps yesterday, reporting out without comment a $4.2 billion bill that is certain to be either killed or significantly amended on the Senate floor.

The version that passed unanimously but without recommendation is alive in form only, its essential provisions scheduled to be removed and replaced on the Senate floor with a hastily drafted substitute from Sen. Jennings Randolph (D-W.Va.) and Robert T. Stafford (R-Vt.), the chairman and ranking minority member respectively of the Environment and Public Works Committee. Their $2.7 billion approach could come to a vote this week.

Finance Committee Chairman Russell Long (D-La.) brought the issue to a vote after only two hours of a scheduled three-day markup in order, he said, to get action on the controversial subject before Congress adjourns. "This legislation should be decided by this Congress and this Senate, and we hope the Senate can act on it in these remaining days," he said.

The Stafford-Randolph substitute, introduced yesterday, is an effort to bring the Finance Committee measure some distance toward a much weaker $1.2 billion superfund that passed the House overwhelmingly in September. Stafford and Randolph then hope the two houses canovercome industry objections and agree on a bill before the clock runs out and Congress adjourns.

Both measures would set up a fund financed 87 percent by a new tax on; the chemical industry and the rest by the federal government to pay for the cleanup of abandoned dumpsites like Love Canal in New York.

But there the resemblance ends. The Stafford-Randolph measure would reimburse victims of such a dump for their out-of-pocket medical expenses. It would provide some financial aid to help victims pay for expert witnesses in lawsuits, and would partially finance diagnostic services, studies of health effects and relocation to new homes, none of which come under the House-passed measure.

It would broaden the House coverage from spills contaminating surface water to include toxic spills on the ground, into groundwater and into the air, and would allow action on them to be taken with fewer bureaucratic steps. However, the compromise eliminated provisions in the original Senate bill assigning strict liability for spills to chemical producers and easing evidence requirements for victims suing chemical companies.

Those were the main objections of the chemical industry and of Senate committee conservatives, several of whom also expressed reservations about the remaining medical compensation section in the compromise approach.

Edmund B. Frost, vice president and general counsel of the Chemical Manufacturers Association, said the effort "is not much of a compromise and we could not support it."

However, Swep Davis of the Environmental Protection Agency's water and waste management division called the bill "basically good" and said the administration "absolutely" would support it as the best deal available this session.